Retractable scarifier



Sept. 27, 1966 Q JONES 3,274,712

RETRACTABLE SCARIFIER Filed April 16, 1964 2 Sheets-Sheet 1 FIG-. 2.

INVENTOR. fiW//fl' 6. MOW 55 Sept. 27, 1966 D. c. JONES RETRACTABLESCARIFIER 2 Sheets-Sheet 2 Filed April 16, 1964 INVENTOR. lV//W' C./0/V5 United States Patent 3,274,712 RETRACTABLE SCARIFIER Dwight C.Jones, La Habra, Calif, assignor to Earthcavator Company, Inc., acorporation of California Filed Apr. 16, 1964, Ser. No. 360,234 1 Claim.(Cl. 37145) This invention relates to earth scarifiers and particularlyto a retractable scarifier of the general type shown in US. LettersPatent to M. C. Davis, et al., US. Patent No. 2,865,117.

This type of scarifier is adapted to be incorporated with a scraperhitched onto the back end of a light tractor and the scarifier ismanually shiftable between a downward position in which the scarifierdigs into the earth when the scraper is pulled forwardly, and aretracted position in which the scarifier is disposed upwardly out ofthe way of using the scraper primarily as a dirt scraping, collectingand spreading tool. The mechanism shown in said patent for manuallyshifting the scarifier between these two positions is located to oneside of the vertical yoke which occupies a substantial portion of thefrontal area of the scraper and which provides attaching points for thethree-point hitch connecting the scraper to the tractor and throughwhich the scraper is pulled and bodily raised or lowered, as desired, bya power take-off on the tractor. The location of the scarifier shiftingmeans a substantial distance from the center of the scraper providesasymmetrical resistance to the stresses set up in the scarifier whichrenders the latter subject to undue strains in operation.

It is accordingly an object of the present invention to provide aretractable scarifier having manual means for shifting the scarifierbetween an upwardly retracted position and a downwardly disposedoperative position and locking the scarifier in the latter positionwhich applies such restraint to the scarifier in the fore-and-aftvertical plane which bisects the scarifier so as to symmetrically resistthe strains imposed upon the scarifier and the scraper supporting thesame by engagement of the scarifier with the earth.

It is a further object of the present invention to provide a draft beamwith a retractable scarifier mounted thereon, wherein the latter, whenin operative position, is locked to said beam at a relatively lowcentral point therein so as to give a direct connection between saidbeam and said scarifier which is close to the points of the scarifierteeth where these dig into the earth.

A further object of the present invention is to provide a retractablescarifier as aforesaid in which the pivotal mounting of the scarifier onits draft beam is on a transverse axis disposed a substantial distanceabove the locking connection formed as aforesaid between mid-points ofsaid scarifier and said draft beam at a relatively low level on thelatter.

It is still another object of the present invention to provide such aretractable scarifier in which the scarifier is pivotally connected tothe aforesaid draft beam along a transverse axis disposed rearwardlyfrom and at a relatively high level with respect to said beam at twowidely spaced points and said scarifier, when in operative position islocked downwardly and forwardly with respect to said beam 'by a hookwhich engages a lower edge of said beam and is located in thefore-and-aft vertical axial plane of the scarifier so as to besymmetrically disposed relative to said points of pivotal connectionbetween said scarifier and said beam.

It is a further object of the present invention to provide such aretractable scarifier in which the mechanism for manually shifting thescarifier between operative and retracted positions is springcounterbalanced to facilitate its being actuated manually.

A further object of the invention is to provide such a scarifier with anadjustable spring counterbalance means whereby the counterbalancingforce applied to the scarifier will be suflicient for merelycoun-terbalancing the weight of the latter when this weight variessubstantially due to varying the number of teeth provided on saidscarifier.

The manner of accomplishing the foregoing objects as well as furtherobjects and advantages will be made manifest in the followingdescription taken in connection with the accompanying drawings in whichFIG. 1 is a front view of a preferred embodiment of the inventionincorporated in a scraper and showing the scarifier in retractedposition.

FIG. 2 is an enlarged sectional view taken on the line 22 of FIG. 1.

FIG. 3 is a fragmentary sectional detail view illustrating the fullopening of the locking hook by the initial movement of the manual meansfor shifting the scarifier from its upward retracted position to itsdownward operative position.

FIG. 4 is a view similar to FIG. 2 with the scarifier shown in loweredoperative position.

FIG. 5 is a fragmentary enlarged detail view showing the detailstructure of one of the adjustable counterbalancing springs of theinvention.

Referring specifically to the drawings, the invention is thereillustrated as embodied in a combination earth scraper and scarifier 5which includes a rectangular scraper bucket 6'having side walls 7 and aback wall 8 connecting rear ends of said side walls, a forwardlyinclined scraper blade 9 being mounted on the lower edge of said backwall. A draft beam 10, disposed transversely within said bucket, has itsopposite ends integrally united as by welding with forward portions ofsaid walls. Said draft beam includes a heavy cylindrical pipe 11 whichis reinforced by angle irons 12 and 13 welded to the front side of saidpipe. IFitting front and upper faces of draft beam 10 and welded theretoso as to extend upwardly therefrom is .an arched draft yoke 14, saidyoke being symmetrically disposed relative to the fore-and-aft axialvertical plane 22 which bisects the bucket '6. A pair of brace bars 15are disposed parallel and in symmetrical relation with said plane theupper ends of said bars being welded to the yoke '14 and their lowerends being welded to draft beam 10. Welded to upper portions of bars 15and extending forwardly therefrom is a pair of apertured bearing lugs16. Welded to yoke 14 and extending upwardly from the central portionthereof is a pair of apertured lugs 17 through which a pin 18 isinserted. The :lower parallel portions '19 of yoke 14 which are weldedto draft beam 10 may be referred to as the feet of said yoke. Welded tobeam 10- in outward-1y parallel spaced relation with yoke feet 19 is apair of hitch attaching lugs 20, said feet and lugs having alignedapertures for receiving hitch attaching pins 21. The combination earthscraper and scarifier 5 is adapted to be drawn behind a Fordson orsimilar light tractor and for this purpose is connected to such atractor by an adjustable hitch element 22 which connects to pin 18 andhitch bars 23 which connect to pins 21.

Spaced inwardly from yoke feet 19 and welded to the top face of draftbeam 10- is a pair of angle brackets 28 these brackets and said yokefeet having aligned aper-.

tures for receiving shafts 29. Rotatably mounted on each of these shaftsis a spring sleeve 30 on which is coiled a heavy spring 31. An end ofeach of said sleeves disposed adjacent one of said yoke feet is providedwith an annular flange 32, said flange having a series of horizontalholes circumferentially arranged therein, any of which is adapted toreceive a pin 33 which is horizontally,

slidably mounted in a suitable hole provided therefor in said yoke foot.The end of each spring 31 adjacent flange 32 of the sleeve 30 on whichsaid spring is wound, is fixed to said sleeve by a pin 34 which extendsdiametrically through aligned apertures in said sleeve and the shaft 29on which the same is mounted. Integral with each spring 30 and extendingupwardly from the inner end thereof is a spring biased arm 35 having aneye 36 formed on its outer end. The purpose of these springs will bemade clear hereinafter.

Welded to draft beam 10 in close parallel spaced relation on oppositesides of vertical plane 2-2 is a pair of :lugs 37 having alignedapertures for receiving a pivot pin 38. Welded in a central location onthe lower forward edge of draft beam :10 is a striker plate 39. Alsowelded to beam 10 to extend rearwardly therefrom in relatively widelyspaced relation on opposite sides of plane 22 are pairs of lugs 40 eachof which pairs has horizontally aligned apertures for receiving a pin 41these pins in both of said pairs of lugs being in coaxial alignment onan axis which is disposed a substantial distance rearwardly from thepipe 11 of draft beam 10 and a substantial distance above the horizontalplane containing the axis of said pipe.

The combination earth scraper and scarifier includes a scarifier 45having a hollow scarifier bar 46 which is approximately square'in crosssection and has flat walls 47, 48, 49 and 50. Walls 47 and 49 areprovided with a series of aligned slots '51 in various pairs of whichscariher teeth 52 are mounted. Each pair of slots 51 may have ascarifier tooth 52 mounted therein or certain of these pairs of slotsmay be left vacant where a particular scarifying job requires the teethto be spaced apart a greater distance than that between adjacent pairsof slots 51. In other words, the scarifier bar 46 may be operated with avarying number of teeth 52 mounted thereon, the fewer the teeth thegreater the distances that adjacent teeth are spaced apart along saidbar.

Welded to flat wall 47 of bar 46, so as to extend between pairs of lugs40, and apertured, so as to receive pins 41 and be pivotally mountedthereon, are lugs 53 each of these lugs having an arcuate face 54 whichfits the curvature of pipe 11 and acts as a stop terminating the upwardswinging movement of scarifier bar 46 about the axis of pins 41 whichdetermines the upward retracted position of said bar as shown in FIG. 2.Welded upon wall 48 of scarifier bar 46 is a pair of short lugs 55 whichare symmetrically spaced on said bar the same distance apart as eyes 36and are pivotally connected by links 56 and coiled springs 57 to saideyes.

The tension on heavy coiled springs 31 is adjusted in accordance withthe number of scarifier teeth 52 mounted on bar 46 so as to yieldablyhold said bar in its upward position shown in FIG. 2.

Welded on flat wall 50 of scarifier bar 46 in parallel closely spacedposition and equidistant from said vertical plane 2-2 is a pair of hookmounting lugs 60 having aligned holes for mounting a heavy pivot pin 61.A massive hook 62 which is preferably made of steel plate about one inchthick slidably fits between lugs 60 and is apertured to receive pin 61so as to be pivotally mounted on said pin between said lugs. A stop rod63- is welded at its ends on lugs 60 to limit the counterclockwiseswinging of said hook at its maximum open position (FIG. 3). Welded to ahub portion of hook 62 and extending approximately in the oppositedirection from pin 62 than said hook is an arm 64 which is preferablymade of steel plate about one-half inch thick, is apertured to receive apin 65 and has a lug 66 to which one end of a contractile spring 6-7connects, said spring extending through suitable apertures provided inscarifier bar 46 with the opposite end of said spring hooking onto saidbar whereby the spring is concealed within said bar and yieldably urgeshook 62 to rotate clockwise into hooking position (FIG. 4).' A pair ofquarter inch thick plates 68, lying flat against opposite sides of arm64, and pivota-lly connected thereto by pin 65, are united by beingwelded to a stop block 69 with the latter disposed beneath the extremityof arm 64 and between this arm and scarifier bar 46. The plates 68comprise a link 70 the opposite end of which is pivotally connected to alink 71 which extends between plates 68 and is pivotally connectedthereto by a pin 72.

The opposite end of link 71 is pivotally connected by a pin 73 to theupper end of a link 74 the lower end of which extends between lugs 37and is pivotally mounted on pin 38 provided in said lugs.

Extending through the apertured ends of bearing lugs 16 is a shaft 75 onwhich a sleeve '76 disposed between said lugs is rotatably mounted, saidsleeve having a pair of lever arms 77 welded thereto near the oppositeends of said sleeve so as to extend forwardly therefrom as shown in FIG2. The free ends of arms 77 are pivotally connected to a pair of off-setlinks 78 which extend downwardly and inwardly with their lower endsembracing the pivotally connected ends of links 74 and 71 therebetweenand being pivotally connected to said ends of said links by pin 73.Welded on one of the lever arms 77 is a hand lever 79.

Operation It is to be understood that the device 5 of the presentinvention is connected by hitch element 22 and hitch bars 23 to the backend of a tractor, the operator of which is seated just forward of thehand lever 79 so that he may readily reach back and engage this leverwith his hand any time he desires to shift the scarifier 45 from itsinoperative position as shown in FIG. 2 to its operative position asshown in FIG. 4 or vice versa. To perform the first of these acts, theoperator seizes hand lever '79 in the position in which this is shown inFIGS. 1 and 2 and swings it forwardly into the position in which this isshown in FIG. 4. The first result of this movement of hand lever 79 isto shift link 71 in the direction of arrow 80 (FIG. 3) and the firstpart of this movement rocks the hook 62 into its maximum open positionas shown. When the hook 62 is thus brought against stop rod 63, themovement of link 71 is transmitted to the scarifier bar 46 so that thebalance of the movement of link 71 in response to the downward andforward swinging of hand lever 79 is to swing the scarifier barsubstantially into the downward position in which this is shown in FIG.4. The friction between the stop block 69 and scarifier bar 46, causedby the pressure of the link 71 against said block during the initialpart of this downward swinging of the scarifier bar, causes the hook 62to continue to be held in its open position practically until thescarifier bar reaches its downward position shown in FIG. 4, whereupon arelaxation of manual pressure on the hand lever 79 reduces the frictionbetween stop block '69 and scarifier bar 46 and permits the hook 62 torespond to the action of contractile spring 67 thereby snapping the hook62 from its open position, shown in FIG. 3, to its closed position shownin FIG. 4.

It is to be noted that the extremities of hook mounting lug 60 areprovided with arcuate faces 81 which fit against the curved outersurface of the draft beam pipe 11 when the scarifier bar 46 is in itsdownward position shown in FIG. 4. This produces a solid locking of themiddle of the scarifier bar to the draft beam 10 against either.

forward or backward movement relative to said beam until the operator,by shifting the hand lever 79 upwardly, withdraws the hook 62 fromlocking relation with draft beam 10. The latter action is accomplishedby the initial upward movement of hand lever 79 from the position inwhich this is shown in FIG. 4. This movement of course.

shifts the link 71 upwardlywhich pulls upward on the end of link 70which includes stop block 69, and as the latter underlies the free endof hook arm 64, the upward movement of link 70 swings the hook 62 bodilyabout its pivotal mounting pin 61 untilthe hook 62 completely disengagesstriker plate 39 and swings against stop rod 63 so that the balance ofthe upward movement of link 71 is effective, with the assistance of theheavy coiled springs 31, to swing the scarifier bar 46 from its downwardto its upward position as shown in FIG. 2.

The tension of the coiled springs 31 is preferably adjusted inaccordance with the number of scarifier teeth 52 mounted on the bar 45so that the latter will be snugly retained in its upward position asshown in FIG. 2 without the necessity of locking said bar in thisposition. The spring pressure provided by springs 31 holds the arcuatefaces 54 provided on lugs 53 snugly against the draft beam pipe 11 thusplacing the scarifier 45 in its retracted upward position so as not tointerfere with the various other earth moving operations which thedevice 5 is provided for performing and which do not involve the use ofthe scarifier 45.

Included among the advantageous features of the present invention whichcontribute to its remarkable ruggedness are the following: thesymmetrical location of the means for locking the scarifier bar inoperative downward position so that it will provide balanced support forall parts of the scarifier 45; division of the draft forces transmittedthrough the draft beam to the scarifier bar 46 between the widely spacedpairs of pivotal mounting lugs 40 and 53, on the one hand, and a massivecentral steel hook 62 and means for massively mounting the same on thescarifier bar, on the other hand; providing for the draft beam 10 beingengaged by said hook directly in the fore-and-aft vertical axial plane22 of the invention; providing a substantial spacing between the pointof contact between said hook and said draft beam and the transverse axison which the scarifier bar pivotal mounting lugs 40 and 53 areconnected; and the provision of linkage which automatically retractssaid hook and maintains it in non-locking position until the moment thatthe scarifier bar reaches its downward position and then automaticallycausing the hook to snap into its snug locking position; and theautomatic retraction of the hook from its locking position with relationto the draft beam as the first step in the action of the manuallyoperated linkage for returning the scarifier 45 from its downwardoperative position to its upward retracted position.

While only a single embodiment of the invention has been disclosedherein, it is to be understood that this is for illustrative purposesonly and that this specific embodiment is subject to numerous changesand modifications without departing from the spirit of the invention orthe scope of the appended claim.

What is claimed is:

A scarifier embodied in an earth scraping tool drawn by a poweredtractor, said scarifier comprising: a draft beam adapted to be supportedrigidly at its opposite ends on said tool; a scarifier bar having teethattached thereto, said bar being arranged parallel with and generallyrearwardly from said beam; pivotally connected lugs fixed on said beamand said bar at symmetrically spaced points thereon for pivotallymounting said bar on said beam on a transverse axis disposed betweensaid bar and said beam whereby said bar is swingable between a downwardteeth extending position and an upward teeth retracting position;striker plate means provided upon a forward lower edge of said beam;hook means disposed symmetrically with the central vertical fore-and-aftaxial plane of said tool and pivotally mounted on said bar on atransverse axis between said striker plate means and said hat when thelatter is in downward position, said hook means being adapted to hookupwardly over said striker plate means when said bar is swung into itsdownward position; an arm integral with said hook means and extendingrearwardly therefrom above said bar when the same is in downwardposition; spring means rotatively biasing said hook means and said armabout the axis of their pivotal mounting to move said hook means intohooking relation with said striker plate means when said bar is indownward position; a stop on said bar for limiting rotation of said hookmeans and said arm in an opposite direction and to a degree slightlypast that necessary to unhook said hook means from said striker platemeans; a first link, one end of which is pivoted to said arm close tothe place where said arm is integrally joined with said hook means andon an axis above said bar when the same is in downward position, saidlink then extending rearwardly across said bar and having a lugunderlying said arm whereby lifting on said link will lift on said armand Swing said hook means against said stop; a second spring meansrelatively biasing said bar to rotate the same from its downwardposition to its upward position when said hook means is swung againstsaid stop; and toggle means for applying power to swing said bar againstthe action of said second spring means and into its downward position,said means including a second link extending downwardly therefrom andpivotally joined at an obtuse angle at its lower end with the rearextremity of said first link when said bar is in its upward positionwhereby actuation of said toggle means to push said second link downwardrotates said hook means and arm against the action of said first springmeans and swings said hook means into engagement with said stop,whereupon further downward movement of said second link swings said baragainst the action of said second spring means and into the downwardposition of said bar where a change thus caused in the angular relationbetween said links renders the first spring means effective in swingingsaid hook means upwardly into hooking relation with said striker platemeans.

References Cited by the Examiner UNITED STATES PATENTS 1,285,900 11/1918Bartholomew 172-269 1,854,904 4/1932 Johnson 172-269 X 2,555,555 6/1951Olson et al 172-269 2,839,851 '6/1958 Geiszler 37--145 2,865,117 12/1958Davis et a1. 37145 FOREIGN PATENTS 899,731 12/1953 Germany.

352,851 7/1931 Great Britain.

639,151 6/ 1950 Great Britain.

ABRAHAM G. STONE, Primary Examiner.

JOE O. BOLT, WILLIAM A. SMITH III, Examiners.

